32-channel arrayed waveguide grating multiplexer using low loss fluorinated polymer operating around 1550 nm

A 32 × 32 arrayed waveguide grating (AWG) multiplexer operating around the 1550 nm wavelength has been designed and fabricated using highly fluorinated polyethers. The propagation loss of the slab waveguide is about 0.3 dB/cm at 1550 nm wavelength. The channel spacing of the AWG multiplexer is 0.8 nm (100 GHz). The insertion loss of the multiplexer is 10.3-15.3 dB and the crosstalk is less than −20 dB.     

Analysis for fabrication errors of arrayed waveguide grating multiplexers

Based on the transmission theory, parameter optimization is performed, and effects of fabrication errors on transmission characteristics are analyzed for a 33×33 polymer arrayed waveguide grating (AWG) multiplexer around the central wavelength of 1550.918 nm with the wavelength spacing of 0.8 nm. Simulated results show that fabrication errors result in the shift of the transmission spectrum, and lead to the increase of the crosstalk compared with the device theoretically designed. Furthermore, accumulation and compensation of fabrication errors are investigated. In order to realize the normal demultiplexing of the fabricated AWG device, the allowed fabrication errors are discussed.     

Design and fabrication of arrayed waveguide grating using fluoropolymer PFS-co-GMA

A 33×33 polymer arrayed waveguide grating (AWG) multiplexer is optimized and fabricated. This device is made of polymeric materials named 2,3,4,5,6-pentafluorostyrene-co-glycidylmethacrylate (PFS-co-GMA). The central wavelength and wavelength spacing are designed to be 1550.918 and 0.8 nm, respectively. The calculated results are: the 3-dB bandwidth is about 0.24 nm, insertion loss is about 8.4 dB and crosstalk is −33.7 dB. The corresponding measured results are: the center wavelength is about 1550.85 nm, wavelength channel spacing is about 0.81 nm, 3-dB bandwidth is about 0.35 nm, crosstalk is about −20 dB, insertion loss is between 10.4 dB for the central port and 11.9 dB for the edge ports.     

Arrayed waveguide grating multiplexer with high thermal stability on silicon

In this paper, certain important parameters are optimized for a polymer/Si arrayed waveguide grating (AWG) multiplexer by using grating theory. A 32-channel multiplexer is designed and fabricated using newly synthesized fluorinated poly (ether ether ketone) with a high thermal stability. The measured wavelength channel spacing is 0.796 nm, and center wavelength and 3-dB bandwidth are 1548 nm and 0.3 nm, respectively.     

Athermal silicon arrayed waveguide grating with polymer-filled slot structure

In this paper, an athermal silicon arrayed waveguide grating (AWG) with the assistance of a polymer-filled slot structure is proposed. Arrayed slot waveguides were used to replace arrayed silicon photonic wires (SPWs). By carefully controlling the temperature dependence of the effective index of the polymer-filled slot waveguides, the athermal silicon AWG is realized. Analysis shows that the center wavelength shift of the AWG can be down to 0.14 pm/°C.     

Compact SOI arrayed waveguide grating demultiplexer with broad spectral response

A compact eight-channel flat spectral response arrayed waveguide grating (AWG) multiplexer based on silicon-on-insulator (SOI) materials has been fabricated on the planar lightwave circuit (PLC). The 1-dB bandwidth of 48 GHz and 3-dB bandwidth of 69 GHz are obtained for the 100 GHz channel spacing. Not only non-adjacent crosstalk but also adjacent crosstalk are less than −25 dB. The on-chip propagation loss range is from 3.5 to 3.9 dB, and the total device size is 1.5 × 1.0 cm².     

650 nm聚合物阵列波导光栅波分复用器设计

选择在可见光波段具有较低吸收损耗的聚甲基丙烯酸甲酯-甲基丙烯酸环氧丙酯 共聚物作为波导包层材料,使用双酚A型环氧树脂作为折射率调节剂,根据材料的折射率设计了单模波导截面尺寸;然后,采用束传播法优化设计出16信道阵列波导光栅(AWG)器件的版图结构。利用Optiwave软件模拟了AWG器件的光传输特性,结果显示,器件的信道间隔为0.845 01 nm,插入损耗小于14 dB,串扰小于-25 dB。     

System degradation due to phase error induced crosstalk in WDM optical networks employing arrayed waveguide grating multi/demultiplexer

The phase error induced crosstalk within arrayed waveguide gratings (AWG) have been investigated theoretically as well as simulation. For WDM system, a crosstalk level of −21.9 dB causes a power penalty of 1 dB for 64 channels and less than 0.5 dB for 16 channels and 32 channels, respectively. For crosstalk level of −30 dB and below, the power penalty is negligible. Crosstalk due to phase error also causes higher power penalty at higher bit rate. Bit rate of 10, 20 and 40 Gbits/s causes power penalty of 1 dB with crosstalk level of −41.5, −46.25 and −49 dB, respectively.     

Performance analysis of metro WDM network based on an optical cross connects and arrayed waveguide grating demultiplexer

In this paper, we have demonstrated the quality-of-service offered by the metropolitan area network which is based on optical cross connect (OXC) and arrayed waveguide grating (AWG) demultiplexer operating at 10 Gb/s with 0.1 nm channel spacing for NRZ signal transmission. The data is successfully transmitted to a distance of 40 km with a reasonably good BER of 2.388 × 10⁻³⁵. The OXC and AWG demultiplexers in the proposed architecture allow incremental expansion in terms of the number of wavelength channels to be transmitted. Dispersion and crosstalk are the main signal-degrading factors arising from the operation of the OXC and the effectiveness of each factor is individually investigated.     

Novel wavelength-accurate InP-based arrayed waveguide grating

A 13-channel, InP-based arrayed waveguide grating （AWG） is designed and fabricated in which the on-chip loss of the central channel is about -5 dB and the crosstalk is less than -23 dB in the center of the spectrum response. However, the central wavelength and channel spacing are deviated from the design values. To improve their accuracy, an optimized design is adopted to compensate the process error. As a result, the central wavelength 1549.9 nm and channel spacing 1.59 nm are obtained in the experiment, while their design values are 1549.32 nm and 1.6 nm, respectively. The route capability and thermo-optic characteristic of the AWG are also discussed in detail.     

A novel asymmetric arrayed waveguide grating with different lengths of input/output slabs

A novel arrayed waveguide grating (AWG) with asymmetric configuration is proposed. In this configuration, the length of the output slab region, the width and the spacing of the output waveguides are unequal to the corresponding parts of the input ones. Compared to a conventional symmetric AWG, the asymmetric AWG proposed in this paper has a smaller size without degrading its performance The analytic method used in a conventional symmetric AWG is extended to the asymmetric AWG. A design example of an asymmetric AWG with low insertion loss, low channel crosstalk and wide bandwidth is presented.     

Parameter optimization and structural design of polymer arrayed waveguide grating multiplexer

First some important parameters are optimized for the structural design of a polymer arrayed waveguide grating (AWG) multiplexer around the central wavelength of 1.55 μm with the wavelength spacing of 1.6 nm. These parameters include the thickness and width of the guide core, mode effective refractive indices and group refractive index, diffraction order, pitch of adjacent waveguides, length difference of adjacent arrayed waveguides, focal length of slab waveguides, free spectral range (FSR), the number of input/output (I/O) channels, and that of arrayed waveguides. Then the bent angles, radii and lengths of all the input/output channels and arrayed waveguides are determined. Finally, a schematic waveguide layout of this device is presented, which contains 2 slabs, 11 input channels, 11 output channels, and 91 arrayed waveguides.     

Design of flat-field arrayed waveguide grating with three stigmatic points

A new-type flat-field arrayed waveguide grating (AWG), with the focal signals of all wavelengths of operation focusing along a straight line, has been designed. The work bases on the aberration theory of AWG, in which the restraints imposed on the conventional Rowland-type AWG have been released. In the design of flat-field AWG, three stigmatic points restrain three dominant geometry parameters: geometry of star couplers, ports distribution of phased-array, and length increment between adjacent paths. An eight-channel 200-GHz spacing flat-field AWG has been designed and simulated. As stigmatic points introduced, the aberration of this device is much lower than that of the Rowland-type AWG.     

Modeling of arrayed waveguide grating for wavelength interrogation application

We have proposed and discussed a design of arrayed waveguide grating (AWG) for the application of wavelength interrogation. The spectral responses of a silica-based 16 channel AWG with channel spacing 1.6 nm have been simulated when different receiver waveguide spacing are used. It was found that the 3-dB bandwidth is reduced about 50% as the receiver waveguide spacing increasing from 20 μm to 30 μm. The effect of bandwidth of the spectral response on wavelength resolution of AWG based interrogator has been estimated and discussed.     

阵列波导光栅梳状带通滤波器的传输效率

在光波导模场分布高斯近似条件下,根据星形光波导耦合器的耦合特性,推导出了基于累加运算和卷积运算近似表达的阵列波导光栅梳状带通滤波器光谱响应效率的函数表达式。给出了阵列波导光栅梳状带通滤波器光谱响应效率曲线的半最大值全宽度和阵列波导光栅梳状带通滤波器的通道中心波长的光谱响应度与器件参数的关系。在输入信号光谱分布高斯近似条件下,给出了阵列波导光栅梳状带通滤波器信号通道传输效率的计算表达式和输入信号光谱宽度对阵列波导光栅梳状带通滤波器信号通道输出特性的影响。给出了物理意义明确的函数表达式,它们可为快速分析阵列波导光栅梳状带通滤波器的特性提供理论基础。     

Design and fabrication of multi-channel photodetector array monolithic with arrayed waveguide grating

We have provided optical simulations of the evanescently coupled waveguide photodiodes integrated with a 13-channels AWGs. The photodiode could exhibit high internal efficiency by appropriate choice of layers geometry and refractive index. Aseamless joint structure has been designed and fabricated for integrating the output waveguides of AWGs with the evanescently coupled waveguide photodiode array. The highest simulation quantum efficiency could achieve 92% when the matching layer thickness of the PD is 120 nm and the insertion length is 2 μm. The fabricated PD with 320-nm-thick matching layer and 2-μm-length insertion matching layer present a responsivity of 0.87 A/W.     

Single-mode rib polymer waveguides and electro-optic polymer waveguide switches

Mode-matching and effective index methods are used to analyze single-mode operation of optical rib polymer waveguides. Their single-mode waveguiding conditions are determined. Single-mode rib waveguides fabricated from guest–host polyetherketone are presented. The estimated propagation loss of straight rib-waveguides is 0.7 dB/cm at 1.55 μm. Furthermore, by using the mode field-transfer matrix method, 2×2 and 4×4 polymer Mach–Zehnder interference switch operating at 1.55 μm wavelength has been designed based on optical multi-mode interference.     

A concise design of 16 × 16 polymer AWG with low insertion loss and crosstalk

In this paper, a 16-channel arrayed waveguide grating multiplexer (AWG) has been designed using polymer materials with 1.5% refractive index difference. Certain important parameters are optimized using the coupling mode theory and Beam Propagation Method. The factors that affect the insertion loss and the crosstalk are analyzed in this paper. In our design we introduced the parabolic taper structure and evaluated the suitable number of the arrayed waveguide, obtaining a total insertion loss of 2.19 dB. For obtaining a low crosstalk we evaluate the pitches of adjacent input/output waveguides ΔX and arrayed waveguides d as different values. We chose the value of ΔX about 2.5 times of d by enlarging the pitches of adjacent input/output waveguides. The crosstalk of the designed AWG is lower than −40 dB.     

A 32-channel 100 GHz wavelength division multiplexer by interleaving two silicon arrayed waveguide gratings

A 32-channel wavelength division multiplexer with 100 GHz spacing is designed and fabricated by interleaving two silicon arrayed waveguide gratings (AWGs). It has a parallel structure consisting of two silicon 16-channel AWGs with 200 GHz spacing and a Mach-Zehnder interferometer (MZI) with 200 GHz free spectral range. The 16 channels of one silicon AWG are interleaved with those of the other AWG in spectrum, but with an identical spacing of 200 GHz. For the composed wavelength division multiplexer, the experiment results reveal 32 wavelength channels in C-band, a wavelength spacing of 100 GHz, and a channel crosstalk lower than -15 dB.     

紫外固化型聚合物高阶布拉格波导光栅滤波器

利用紫外固化材料SU-82005与热交联聚合物甲基丙烯酸甲酯一甲基丙烯酸缩水甘油酯[P（MMA—GMA）]分别作为波导芯层和包层材料,通过直接光刻技术,成功实现了厚度为5μm,宽度为9μm,光栅高度为4μm的起伏型高阶布拉格波导光栅滤波器。对光栅器件的谐振波长,光透射率等重要参数进行了模拟设计。测得制备的聚合物高阶布拉格波导光栅滤波器的谐振波长为1550．4nm,消光比为23dB,3-dB带宽为2nm。